Alternating Current

In the part of an a.c. circuit as shown, the resistance \(R=0.2 \Omega\). At a certain instant \((\mathrm{V_A-V_B})= 0.5 \mathrm{~V}, \mathrm{I}=0.5 \mathrm{~A}\) and \(\frac{\Delta \mathrm{I}}{\Delta \mathrm{t}}=8 \mathrm{~A} / \mathrm{s}\). The inductance of the coil is